QC/T 243-2018Flatness requirements and test methods for vehicle wheel mounting faces (English PDF)

4.1 Flatness requirements for attachment face of commercial vehicle wheel

Flatness requirements for attachment face of commercial vehicle wheel See Table 1 for flatness requirements of commercial vehicle wheel attachment face. See Table 2 for measuring area requirements of attachment face.

4.2 Flatness requirements for attachment face of passenger vehicle wheel

See Table 3 for flatness requirements for attachment face of passenger vehicle wheel.

6.1 Gap method I

6.1.1 Measuring gauge for testing

The flat plate flatness shall be less than or equal to 0.02 mm.

6.1.2 Test method

This test method is to use feeler gauge to measure the gaps BETWEEN some positions within the measuring area of attachment face AND flat plate, then take the maximum value as the flatness. Measure according to the following steps:

a) Put the flat plate on the wheel attachment face to make the flat plate cover the measuring area, see Figure 1;

b) Use feeler gauge to measure the gaps between the flat plate and the measuring area of attachment face. Measure at least 8 gaps for commercial vehicle wheel, 4 for outer ring and 4 for inner ring. For passenger vehicle, it shall measure each facet. Record the maximum gap;

NOTE: When cross-shaped flat plate is used, the number of flat plate rotation shall not be less than twice.

c) Take the maximum gap as the flatness of wheel attachment face.

6.2 Gap method II

6.2.1 Testing device

Testing gauge consists of flat plate (circular ring shape) and dial indicator. The flat plate shall be able to cover measuring area. Its flatness shall be less than or equal to 0.02 mm.

6.2.2 Test method

This test method is to use dial indicator to measure the gaps BETWEEN some positions within the measuring area of attachment face AND flat plate, then take the maximum value as the flatness. Measure according to the following steps:

a) Place the flat plate that is equipped with dial indicator on base plane for zero-setting;

b) Place the flat plate on the wheel attachment face. Put the dial indicator within the measuring area of attachment face. Record the difference between dial indicator hand and zero position, see Figure 2;

c) Move the flat plate. Repeat the above step b). For commercial vehicle wheel, it shall select not less than 20 points in a scattering way within the measuring area of attachment face. Not less than 2 points are selected within each facet of passenger vehicle wheel. For passenger vehicle wheel, it shall select not less than 20 points in a scattering way within the measuring area of attachment face;

d) Take the maximum difference hmax between dial indicator hand and zero position as the flatness of attachment face.

1 - dial indicator; 2 - pull handle; 3 - carry handle; 4 - wheel; 5 - flat plate; 6 - sliding block

Figure 2 - Testing diagram of gap method II

6.3 Indicator method

6.3.1 Testing device

Coordinate measuring machine.

6.3.2 Test method

This test method is to use coordinate measuring machine to measure the amount of deviation between the measuring area of attachment face and the measuring base plane so as to evaluate the flatness. Measure according to the following steps:

a) Put the wheel on the workbench of coordinate measuring machine;

b) Within the measuring area of attachment face, randomly take three far points to fit the base plane;

c) Move the measuring pointer. Measure the data of other points. Record the reading of each point hi. It is positive when it is higher than the base plane, negative when lower than the base plane. The points to be taken shall be scattered as much as possible. Take not less than 20 points for commercial vehicle wheel. Not less than 2 points shall be selected within each facet for passenger vehicle wheel. For light alloy wheel of passenger vehicle, it shall select not less than 20 points in a scattering way within attachment face;

d) Take the difference between the maximum reading hmax and the minimum reading hmin as the flatness of wheel attachment face.